Lustreware is a ceramic decorative technique invented by 9th century AD Abbasid potters of the Islamic Civilization, in what is today Iraq. The potters believed that making lustreware was truly "alchemy", because the process involves using a lead-based glaze and silver and copper paint to create a golden shine on a pot that contains no gold.
Lustreware and the T'ang Dynasty
Lustreware grew out of an existing ceramic technology in Iraq, but its earliest form was clearly influenced by T'ang dynasty potters from China, probably first through trade and diplomacy along the vast trade network called the Silk Road. As a result of ongoing battles for control of the Silk Road connecting China and the West, T'ang dynasty potters and other craftsmen were captured and held in Baghdad between AD 751 and 762.
We know about these events because one of the captives was Tou Houan. Tou was a Chinese potter captured from his workshop near Samarkand by members of the Islamic Abbasid Dynasty after the Battle of Talas in AD 751. Tou stayed in Baghdad for some years. When he returned to China, he wrote to the emperor that he and his colleagues taught the Abbasid craftsmen the important techniques of paper-making, textile manufacture, and gold-working. While Tou Houan didn't specifically mention pottery decoration (or silk-making for that matter), it is quite likely that he transmitted how to make white glazes and the fine ceramic pottery called Samarra ware. It's quite likely that he also passed along the secrets of silk-making, but that's another story entirely.
What We Know of Lustreware
The secret to lustreware developed over the centuries, but was kept within one small group of potters who traveled together within the Islamic state until the 12th century, when three separate groups began their own potteries. One member of the Abu Tahir family of potters was Abu'l Qasim bin Ali bin Muhammed bin Abu Tahir. In the 14th century, Abu'l Qasim was a court historian to the Mongol kings, where he wrote a number of treatises on various subjects. His best known work is The Virtues of Jewels and the Delicacies of Perfume, which included a chapter on ceramics, and, most importantly, describes part of the recipe for lustreware.
Abu'l Qasim wrote that the successful process involved painting copper and silver onto glazed vessels, and then refiring to produce the lustrous shine. The alchemy--excuse me, the chemistry--of the lustreware process was identified by a group of archaeologists and chemists, who reported on their investigations into the nanomechanics of lustreware in 2008, in the Journal of Archaeological Sciences.
- Read more about the Invention of Lustreware
Chronology of Lustreware
- Abbasid 8th c -1000 Basra, Iraq
- Fatimid 1000-1170 Fustat, Egypt
- Tell Minis 1170-1258 Raqqa, Syria
- Kashan 1170-present Kashan, Iran
- Spanish (?)1170-present Malaga, Spain
- Damascus 1258-1401 Damascus, Syria
The Science of Alchemy
Additional studies reported by the research team in 2010 and 2012 involved the examination of the chemical content of glazes and the resulting colored lusters of pots from the 9th through 12th centuries. Guiterrez et al. found that the golden metallic shine only occurred when there are dense nanoparticulated layers of glazes, several hundred nanometers thick, which enhance and broaden the reflectivity, shifting the color of the reflected light from blue to green yellow (called a redshift).
These shifts are only achieved with a high lead content, which potters deliberately increased over time from Abassid (9th-10th centuries) to Fatimid (11th-12th centuries) luster productions. The addition of lead reduces the diffusivity of copper and silver in the glazes and helps the development of thinner luster layers with a high volume of nanoparticles. These studies show that although the the Islamic potters may not have known about nanoparticles, they had tight control of their processes, refining their ancient alchemy by tweaking the recipe and production steps to achieve the best high reflecting golden shine.
See the photo essay Islamic Lustrewares: Origins and Technique for more detailed information and photographs.
Caiger-Smith A. 1985. Lustre Pottery: Technique, tradition, and innovation in Islam and the Western World. London: Faber and Faber.
Caroscio M. 2010. Archaeological Data and Written Sources: Lustreware Production in Renaissance Italy, a Case Study. European Journal of Archaeology 13(2):217-244.
Gutierrez PC, Pradell T, Molera J, Smith AD, Climent-Font A, and Tite MS. 2010. Color and Golden Shine of Silver Islamic Luster. Journal of the American Ceramic Society 93(8):2320-2328.
Jenkins M. 2006. Raqqa Revisited: Ceramics of Ayyubid Syria. New York City: Metropolitan Museum of Art.
Molera J, Bayés C, Roura P, Vrespo D, and Pradell T. 2007. Key Parameters in the Production of Medieval Luster Colors and Shines. Journal of the American Ceramic Society 90(7):2245-2254.
Pradell T, Climent-Font A, Molera J, Zucchiatti A, Ynsa MD, Roura P, and Crespo D. 2007. Metallic and nonmetallic shine in luster: An elastic ion backscattering study. Journal of Applied Physics 101(10):103518.
Pradell T, Molera J, Pantos E, Smith AD, Martin CM, and Labrador A. 2008. Temperature resolved reproduction of medieval luster. Applied Physics A: Materials Science & Processing 90(1):81-88.
Pradell T, Molera J, Smith AD, and Tite MS. 2008. Early Islamic lustre from Egypt, Syria and Iran (10th to 13th century AD). Journal of Archaeological Science 35(9):2649–2662.
Pradell T, Molera J, Smith AD, and Tite MS. 2008. The invention of lustre: Iraq 9th and 10th centuries AD. Journal of Archaeological Science 35(5):1201-1215.
Pradell T, Pavlov RS, Gutierrez PC, Climent-Font A, and Molera J. 2012. Composition, nanostructure, and optical properties of silver and silver-copper lusters. Journal of Applied Physics 112(5):054307-054310.
Watson O. 2004. Ceramics from Islamic Lands. New York: Thames and Hudson.